Internet services are available today, utilizing, for example, standard wireless protocols such as Cellular Digital Packet Data, also known as “wireless Internet Protocol” (wireless IP). (See CDPD System Specification and Implementation Guidelines, Release 1.1, Wireless Data Forum, Washington, D.C.) CDPD can be implemented in American Mobile Phone Systems (AMPS) cellular networks, and thus a wireless Internet service based thereon could become widely available, but the service is slow (given a data transmission rate of 19.2 kbps) and expensive (approximately $1.40 per megabyte of data transmitted). (The AMPS is a frequency division multiple access (FDMA) analog cellular system developed by AT&T Bell Labs in the 1970s).
Additionally, wireless local area networks (WLANs), for example, those based on the IEEE 802.11 standard, are emerging. (For further information regarding the IEEE 802.11 standard, refer to IEEE 802.11, 1999 Edition (ISO/IEC 8802-11: 1999) IEEE Standard, for Information Technology—Telecommunications and Information Exchange between Systems—Local and Metropolitan Area Network—Specific Requirements—Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications; IEEE 802.11a-1999: 8802-11:1999/Amd 1:2000(E)), IEEE Standard for Information technology—Telecommunications and information exchange between systems—Local and metropolitan area networks—Specific requirements—Part 11. Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY)>specifications—Amendment 1: High-speed Physical Layer in the 5 GHz band; and IEEE 802.11b-1999: Supplement to 802.11-1999, Wireless LAN MAC and PHY specifications. Higher speed Physical Layer (PHY) extension in the 2.4 GHz band.)
WLANs currently offer peak instantaneous data rates of 11 Mbps (802.11b) or 54 Mbps (802.11b) over a range of approximately 100 meters. Despite the relatively high data rates achieved by IEEE 802.11 based WLANs, such WLANs have no standardized billing or service fee system. This lack of monetary incentive has limited the installation of 802.11 networks for public use. Thus coverage is primarily limited to private networks.
In summary, the wireless Internet service available today is an expensive, fragmented service with limited coverage. To obtain reasonable data transmission rates and service coverage, one could maintain a CDPD subscriber account, and carry a CDPD PCMCIA modem card, and an 802.11b WLAN PCMCIA card. A portable computer would utilize the 802.11b WLAN PCMCIA card for free in the home and office. It would utilize the 802.11b WLAN PCMCIA card for a fee at each hot-spot travel location such as airports and some hotels. The portable computer would use the CDPD PCMCIA modem card for general use outside the home or office. Access to the CDPD network incurs additional fees to yet another operator.
Network operators have not embraced development of a wireless infrastructure because of the perceived need to acquire sufficient licensed radio frequency spectrum to build out a nation-wide network, a costly undertaking. With the uncertainties raised by the introduction of other technologies such as GPRS/EDGE and CDMA-2000, and the recent history of the wireless market, these operators are proceeding slowly and cautiously.
What is needed is a business model, network architecture and protocols that facilitate development and operation of a wireless infrastructure to provide ubiquitous wireless Internet access.